Long Range Arena: A Benchmark for Efficient Transformers

TL;DR

This paper introduces the Long Range Arena benchmark to systematically evaluate efficient Transformer models on long-sequence tasks across multiple data types, addressing inconsistencies in current benchmarking practices.

Contribution

It proposes a unified benchmark suite for long-range Transformers, evaluates ten models systematically, and promotes standardized assessment in this research area.

Findings

Efficient Transformers show varied performance across tasks.

Benchmark reveals strengths and weaknesses of different models.

Provides a platform for future research and model improvement.

Abstract

Transformers do not scale very well to long sequence lengths largely because of quadratic self-attention complexity. In the recent months, a wide spectrum of efficient, fast Transformers have been proposed to tackle this problem, more often than not claiming superior or comparable model quality to vanilla Transformer models. To this date, there is no well-established consensus on how to evaluate this class of models. Moreover, inconsistent benchmarking on a wide spectrum of tasks and datasets makes it difficult to assess relative model quality amongst many models. This paper proposes a systematic and unified benchmark, LRA, specifically focused on evaluating model quality under long-context scenarios. Our benchmark is a suite of tasks consisting of sequences ranging from $1K$ to $16K$ tokens, encompassing a wide range of data types and modalities such as text, natural, synthetic images, and mathematical expressions requiring similarity, structural, and visual-spatial reasoning. We systematically evaluate ten well-established long-range Transformer models (Reformers, Linformers, Linear Transformers, Sinkhorn Transformers, Performers, Synthesizers, Sparse Transformers, and Longformers) on our newly proposed benchmark suite. LRA paves the way towards better understanding this class of efficient Transformer models, facilitates more research in this direction, and presents new challenging tasks to tackle. Our benchmark code will be released at https://github.com/google-research/long-range-arena.